Compact portable oxygen concentrator

ABSTRACT

Portable oxygen concentrator elements are described including integrated sensor/accumulator assemblies, new muffler designs, and improved airflow and internal gas connectivity. The result of the elements is an extremely compact, light reliable portable oxygen concentrator that is easy to assemble and relatively inexpensive.

INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS

Any and all applications for which a foreign or domestic priority claimis identified in the Application Data Sheet as filed with the presentapplication are hereby incorporated by reference under 37 CFR 1.57. Thepresent application is a divisional of U.S. application Ser. No.15/608,775, entitled “COMPACT PORTABLE OXYGEN CONCENTRATOR,” filed May30, 2017, the entirety of which is incorporated by reference.

BACKGROUND

The specification relates to oxygen concentrators for personal use andin particular to an extremely compact portable oxygen concentrator.

Oxygen concentrators for providing oxygen rich air for therapeuticpurposes are increasingly popular as alternatives to liquid oxygenvessels and compressed gas cylinders. Such personal oxygen concentratorsexist in both portable form for ambulatory use and stationary form foruse inside the home. To be practical for everyday use by patientsneeding therapeutic oxygen such portable concentrators must be small insize and weight, efficient, reliable and relatively inexpensive. Thesecontradictory attributes may require new approaches to concentratordesign.

SUMMARY

Portable oxygen concentrator elements may be provided that includeintegrated sensor/accumulator assemblies, new muffler designs, andimproved airflow and internal gas connectivity. The result of theelements is an extremely compact, light reliable portable oxygenconcentrator that is easy to assemble and relatively inexpensive.

In a first aspect, a muffler for a gas concentrator may be provided,including a pressure sensitive gas valve; and a housing made from aporous material holding the valve; wherein in the open position gas flowis substantially through an open portion of the valve, and in the closedposition gas flow is directed substantially through the porous housing,muffling the sound produced by the flowing gas.

In one embodiment of the first aspect, the porous housing may be madefrom a sintered material. In another embodiment of the first aspect, theporous housing may be made from a multitude of individual flow channelsor holes. In one embodiment of the first aspect, the pressure sensitiveelement may be a spring, and the pressure closing point may be set bythe spring compression force. In another embodiment of the first aspect,the muffler may be placed in an exhaust outlet of a gas concentrator. Inone embodiment of the first aspect, the open position flow of the valvemay be substantially unrestricted. In another embodiment of the firstaspect, the valve seal may be comprised from one of at least one of thefollowing elements: a ball, a poppet, a face seal.

In a second aspect, a gas connection system for internal gas connectionsin a gas concentrator may be provided, including two gas ports inalignment separated by a linear or radial distance; and, a compliant,linear connector element; wherein when the two ports and the connectorelement are assembled, the two ports are fixed in the concentratorwhereby the connector element connects the ports.

In one embodiment of the second aspect, the connector element may bemade of a compliant material, including an elastomeric tube. In anotherembodiment of the second aspect, the connector element may contain oneof a lead-in chamfer or radius to facilitate assembly. In one embodimentof the second aspect, the ports may be comprised of at least one barb.In another embodiment of the second aspect, the barb edge may be one ofradiused or chamfered to facilitate removal of the tube.

In one embodiment of the second aspect, two sets of separated ports maybe disposed adjacent each other in parallel, and the connector elementmay be a common element that is comprised of a compliant material,including an elastomeric material. In another embodiment of the secondaspect, the compliant connector element may provide vibration isolationbetween the two ports. In one embodiment of the second aspect, the portsmay overlap by length and the distance between them may be radial. Inanother embodiment of the second aspect, one port may be at least oneend part of at least one of a removable adsorber bed inlet receptacle,and a removable adsorber bed outlet receptacle, and on the other end aport may be in fluid communication with a valve or gas flow manifold ofthe gas concentrator.

In a third aspect an assembly for an oxygen concentrator may be providedincluding an accumulator; an oxygen sensor disposed to sample gasdirected to the patient gas outlet of a gas concentrator; a pressuresensor disposed to sample gas in the accumulator; a temperature sensordisposed to sample gas in the accumulator; a breath sensor disposed tosample gas at a patient gas outlet of the gas concentrator; anelectronic circuit, and gas ports to the sensors and the accumulator;wherein the sensors are at least one of assembled onto an electroniccircuit or directly into a body which includes the accumulator volume;and, the circuit is assembled onto the body making at least one ofdirect sealed gas or electrical connections to the sensors.

In one embodiment of the third aspect, the inlet ports may beconnectable to a concentrator valve manifold system. In anotherembodiment of the third aspect, the assembly may further include atleast one of a display or user interface as part of the electroniccircuit. In one embodiment of the third aspect, the assembly may furtherinclude at least one of a gas output filter or cannula connection to thepatient gas path, and associated inlet and outlet ports from the cannulaconnection to the element.

In a fourth aspect, an integrated cooling system for a portable oxygenconcentrator may be provided wherein the ambient air intake is ducted tothe exterior of the concentrator; the air is moved through the system byat least one fan or blower; the discharge air of the air mover isdirected over at least one air compressor element; the discharge air ofthe air mover is directed to the intake port of at least one aircompressor intake gas connection system; and the cooling air dischargevent is integrated into at least one housing panel.

In one embodiment of the fourth aspect, the air mover may be attached tothe concentrator by a compliant member. In another embodiment of thefourth aspect, the compressor air intake gas may be in fluidcommunication with at least one vibration isolation mount of thecompressor. In one embodiment of the fourth aspect, the intake gasconnection system of the air compressor may be comprised of at least onesubstantially 90 degree bend and at least one compliant tubing member.In another embodiment of the fourth aspect, the speed of the air moveris controlled by an onboard microcontroller. In one embodiment of thefourth aspect, the speed of the air mover may be varied based on atleast one system temperature measurement. In another embodiment of thefourth aspect, the system temperature measurement may be comprised of atleast one of the following measurement sensors a compressor temperaturesensor; an oxygen gas temperature sensor; and a circuit boardtemperature sensor.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects and advantages of the embodiments provided herein are describedwith reference to the following detailed description in conjunction withthe accompanying drawings. Throughout the drawings, reference numbersmay be re-used to indicate correspondence between referenced elements.The drawings are provided to illustrate example embodiments describedherein and are not intended to limit the scope of the disclosure.

FIG. 1 shows a simplified block diagram of an exemplary portable oxygenconcentrator;

FIG. 2 shows the external layout of an exemplary portable oxygenconcentrator;

FIGS. 3A, 3B, and 3C show a block diagram and the physical layout of anillustrative embodiment of a sensor/accumulator block assembly;

FIGS. 4A, and 4B show an illustrative embodiment of a muffler;

FIGS. 5A, 5B, 5C, and 5D show an illustrative embodiment of a gasinterconnection element;

FIGS. 6A, 6B, 6C, 6D, and 6E show an alternative illustrative embodimentof a gas interconnection element;

FIG. 7 shows an illustrative embodiment of internal air flow for anexemplary concentrator;

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

Personal use therapeutic oxygen concentrators are increasing inpopularity, both in very small portable form and relatively small,compared to industrial gas concentrators, stationary home devices. Asmall portable personal use concentrator is described in co-pendingapplication U.S. Ser. No. 15/427,948, assigned to the same assignee ofthe current application and incorporated in its entirety by reference,and in which the operation and use of such concentrators is described.Such concentrators because of their small size and intended personaluse, have differing design considerations from large industrialconcentrators intended to produce large quantities of concentratedgasses. For example, in an illustrative embodiment, the portableconcentrator according to the present disclosure may be betweenapproximately 100 and 300 cubic inches in size, between 2 and 7 poundsin weight, and may produce between 600 and 1300 ml/min of concentratedoxygen.

FIG. 1 is directed to the components and connections for an exemplaryportable oxygen concentrator 100. Air is drawn into the gas concentratorthrough air inlet 1 to cool the system and supply the gas separationsystem with ambient air for inlet and to move out the nitrogen richexhaust gas. This air movement may be provided from a fan or blowerlocated at the inlet, exhaust, or centrally in the air pathway. Toachieve proper air flow and cooling a fan or blower in the range of 40mm×40 mm to 100 mm×100 mm may optimally be utilized. A plurality of fansin varying sizes and locations may also be employed in some embodimentsto optimize air flow and minimize noise.

The gas separation system employs pressure, vacuum, or a combinationthereof in certain embodiments. Ambient air is drawn in by thecompressor 2 intake through a filter and through an elongated ortortuous air path to minimize the escape of noise caused by thecompressor. The compressor 2 may be comprised of a multi cylinderreciprocating piston compressor employing pressure or a combination ofpressure and vacuum cylinders, but may also be comprised of multiplecompressors of types including scroll, linear free piston, rotary vane,rotary screw, or diaphragm type compressors.

The pressurized air is discharged from the compressor 2 at a rate ofapproximately 5 SLPM to 15 SLPM per LPM of oxygen produced at a pressureup to 3 bar. The pressurized air is directed to one of two or moreadsorbent beds 3 by one or more valves 9 that may be housed in afeed/waste manifold. The feed/waste valve configuration varies byembodiment and may be comprised of one or more solenoid valves, airpiloted valves, rotary valves, cam actuated valves, or diaphragm valves.The feed/waste valves may be decoupled from the compressor, adsorbentbeds, and other structural components to minimize transmission of noisefrom the valves. The valve fluid path may be connected with compliantmembers to achieve an appropriate level of mechanical isolation and themanifold or valve mounting is additionally isolated from othercomponents. The feed/waste valves 9 additionally direct exhaust nitrogengas from the adsorbent beds to a muffler in a pressure swing adsorptionsystem or to the vacuum pump in a vacuum or pressure vacuum system.

In some embodiments, the adsorbent beds 3 are designed to be removableand replaceable as described in the above incorporated reference.Adsorbent beds may contain at least one adsorbent layer that is directedto water and carbon dioxide removal to prevent contamination of the mainlayer adsorbent. In some embodiments, this material may be comprised ofa desiccant such as activated alumina or silica gel. In alternateembodiments, the pretreatment layer may contain a sodium or lithiumexchanged zeolite. The main layer adsorbent is directed to separateoxygen from nitrogen and may be a lithium exchanged zeolite material.Nitrogen gas is retained in the adsorbent bed, while oxygen gas isallowed to pass through the adsorbent bed into the product valves 10 orproduct valve manifold in one embodiment.

The product valve manifold 10 may include one or more of solenoidvalves, check valves, and orifices to control gas flow. The productmanifold connects to the adsorbent beds and may be decoupled from theadsorbent beds and other structural components to minimize noisetransmission and vibration between valves and other components in thesystem.

In one embodiment, oxygen gas flows from the product manifold 10 to anintegrated assembly that is directed to product gas storage 4, oxygengas concentration measurement, oxygen gas pressure sensing, as welloxygen gas filtration, and oxygen delivery, i.e. a conserver 7. In oneembodiment, the integrated assembly contains multiple pressure sensors11 for various functions including ambient pressure sensing, oxygen gaspressure measurement, and breath pressure or cannula pressuremeasurement.

The control of the gas concentrator is achieved by a programmablecontroller 5. The gas concentrator also contains a user interface 8comprised of one or more buttons to control power state, oxygen flowrate, and additional functions.

Other embodiments additionally contain an LCD display, at least onerechargeable battery, and an integrated oxygen conserving device todeliver oxygen gas synchronously with a patient's onset of inhalation tomaintain clinical efficacy while reducing the amount of oxygen gasdelivered to the patient by a factor of about 2:1 to 9:1.

FIG. 2 shows the exterior of an exemplary portable oxygen concentrator100. Air flow enters at air inlet screen 1 and flows as described toremovable adsorbent beds 3 and air exhaust 13. The gas concentrator ispowered by battery 12, controlled by user interface 8, and oxygen output14. Components of the gas concentrator are contained within housingelement 101, which forms portions of the air flow path, ducting, andventilation paths.

The embodiment of FIG. 2 is designed to be carried by an oxygen patientto supply oxygen during ambulation and is thereby designed to minimizesize and weight while maximizing battery life and oxygen output. Thesize may be less than about 125 cubic centimeters, the weight less thanabout 3 pounds, and the oxygen output greater than about 630 ml/min. Theoxygen output for the exemplary concentrator is actually greater thanabout 1.7 (ml/min oxygen)/(cm{circumflex over ( )}3*lbs). This optimizedoxygen output per size and weight is scalable to reach higher oxygenflow rates for patients requiring higher oxygen delivery rates at theexpense of the proportionally larger size and greater weight.

FIG. 3A represents the gas flow through an embodiment of an integratedsensor block assembly 300. Oxygen gas flows from the adsorbent beds intothe product valve manifold 310, filtered 320 and delivered to thepatient via a cannula 395, or supplied to an adsorbent bed as purge gas.The accumulator 350 serves to buffer the production and delivery andoxygen between the PSA/VSA or other cycle and the oxygen demand from thesystem. The pressure swing adsorption system is controlled by themicrocontroller with inputs from accumulator pressure sensor 340 tocontrol compressor speed and valve timing to maintain target pressureratios and operating parameters. Oxygen delivery to the patient is alsocontrolled by the microcontroller and is dependent on inputs from breathdetection sensor 370 to monitor the patient's breathing rate and onsetof inhalation. The determination of the proper delivery of oxygen to thepatient utilizes ambient pressure sensor 380 to correct bolus deliveryfor ambient pressure conditions. Oxygen concentration is monitored andvia oxygen sensor 360 and oxygen gas temperature sensor 390. Thetemperature sensor may be located within the oxygen gas flow path in oradjacent to the oxygen sensor 360, or in the accumulator 350, or placeto acquire a correlated temperature reading from circuit board 335 orother suitable location. The sensor data and signals are processed andutilized by the microcontroller to maintain proper oxygen production anddelivery over a wide range of environmental conditions, required flowrates, and to compensate for changes in the system during the lifetimeof the equipment.

FIG. 3B depicts a particular embodiment of the integrated sensor blockassembly 300.

In one embodiment, the oxygen conserver valve is an element of theproduct manifold. In this embodiment, the oxygen gas may flowbidirectionally between the product manifold and the sensor blockassembly as it is passed through the product manifold following beingproduced, and then delivered to the patient passing through the oxygenconserving valve, oxygen sensor, and cannula filter assembly. Thelocation of the conserver valve could also be chosen to have the oxygengas delivery located entirely within the sensor block assembly 300.

FIG. 3C is directed to an embodiment of the integrated sensor assembly300. The volume of the assembly serves as the oxygen accumulator 350,fed by port 355, where oxygen is stored to buffer the production anddelivery demands of the pressure adsorption system and the variablepatient breathing rates and flow settings of the device output. In thisembodiment, the pressure sensors 340, 370 and, the temperature sensor390, and LCD display 330 are mounted to circuit board 335, wherein thepneumatic connections are made directly between the sensors and theassembly and the electrical connections are made directly between thecircuit board and the pressure sensors.

Cannula output connection 380 is attached directly to the sensorassembly 300 and additionally contains a filter element to prevent anycontaminants or particulates from being delivered to the patient.

Oxygen sensor 360 port 365 is designed into the integrated assembly andcontains input and output connections to the product manifold that matesdirectly to the circuit board to measure the concentration of the of theoxygen gas. The integration of the oxygen sensor 360 and other sensorseliminates the need for multiple pneumatic connections and tubes betweenthese components where each connection point poses a risk for assemblydefects and leaks over time. Further, the integration of the circuitboard 335 and LCD display 330 eliminate the need for a large number ofwires and connectors since all the signals and data can be transmittedover one common connection to the microcontroller. The elimination ofthese individual connectors and wires reduces cost, assembly time, andrisk of defects in the final product.

FIGS. 4A and 4B depicts an exemplary embodiment of the exhaust muffler410. The muffler is a pressure responsive system that contains a valve420 that opens and closes depending on the gas flow through it.

In the exemplary embodiment, the muffler body 430 is a sintered materiallike low density polyethylene (LDPE) or bronze. The valve 420 shown iscomprised of a spring and ball wherein the high flow of nitrogen richgas released from the adsorbent bed during the blowdown step closes thevalve, FIG. 4B to force the gas through the sintered material to reducethe exhaust noise. When the high flow of gas dissipates, the springreturns the valve to the open state FIG. 4A and the low flow rate purgegas is allowed to flow directly out of the muffler without substantiallypassing through the sintered material. This open flow path preventsbackpressure on the adsorbent bed and maximizes the efficiency of thepurge and regeneration of the adsorbent material.

In alternate embodiments, the muffler material may be comprised of aperforated material, an orifice, mesh material, felt material, or othersuitable material or design to control the rate of blowdown and nitrogengas release when the valve is closed. Additionally, the pressureresponsive valve may be comprised of a poppet, diaphragm, flapper, orother suitable valve design. Alternate embodiments may combine thepressure responsive element and the valve seal into one element such asa molded elastomeric valve with an inherent spring force.

FIGS. 5A, 5B, 5C and 5D show views of exemplary embodiments for adetachable gas connector system that connects an adsorbent bedreceptacle to a feed/waste manifold. Each fitting 510 has a twist lockmechanism 530 to connect to a chassis portion of housing assembly 101, aradial seal mechanism to mate to an adsorbent bed receptacle, and abarbed end 560 shaped for easy tube removal and additionally containinga stop that ensures that the tube 520 is assembled to the same depth onevery assembly to reduce variability and risk of leaks on the finalproduct.

Tube 520 may be a molded elastomeric tube made from a material such assilicone, viton, EPDM, or rubber. The tube may optionally have a chamfer540 or radius on the inner diameter to facilitate installation on to thebarb or fitting. The tube may also optionally have a thickened endsection 550 that ensures the tube will push onto the barb withoutkinking and will add additional resistance to radial expansion withoutadding stiffness and vibration coupling to the entire tube.

In a typical tube to barb connection, the tube/barb interface serves atleast two purposes: pneumatic or hydraulic coupling as well asmechanical retention that occurs from the sharp retaining edge of thebarb interfering with the tube. This connection method allows for fast,low cost connections to be made between pneumatic components. However,given the designed in mechanical interference between the tube and thebarb, the tubes can often be difficult to install and often times evenmore difficult to remove, very often requiring destruction of the tubeif removal from the barb is required. FIG. 5B depicts the gas connectorsystem fully assembled wherein the tube 520 is constrained at eachdistal end to prevent the tube from detaching from the barbs and toprovide precise assembly distance between the two ports and the tube.The captive ends of the tubing allow a tube to barb or fitting designthat does not need to provide mechanical retention to the barb againstthe pressure inside the tube that would typically dislodge the tube ifit were molded from a low durometer material or a thin walled design ordid not have a robust mechanical interference with the barb to preventit from detaching. The tube must only be strong enough in the radialdimension to prevent leaks caused by expansion of thickened end section550 or by rupture of compliant tube section 520. This is facilitated bya radius at the edge of the barb at its maximum diameter where itinterferes with the tube, which would normally engage the tube formechanical retention.

When assembled, the ports of the fittings 510 are fixed in position sothat the tubing creates a compliant connection between two mechanicalelements, but does not lead to variability in assembly or requirerouting of the tubing.

FIG. 5C is an additional example of the gas connector system directed tothe fixed locations of the barb connectors and ports. FIG. 5D showsanother example of such a gas connector system. In this example, oneport is located on the feed/waste manifold of a gas concentrator and theother port is a fitting connected to an adsorber receptacle. Thecompliant tube 520 prevents noise and vibration generated by switchingof the solenoid valves. The feed/waste manifold provides the mechanicalsupport to the tube to barb connections and is affixed to posts onchassis component of housing assembly 101 via rubber grommets.

FIGS. 6A, 6B, 6C, 6D and 6E show views of exemplary embodiments of a gasconnector system designed to connect a product end valve manifold to anintegrated sensor assembly but may alternately be employed in variousother internal gas connections within a gas concentrator.

FIG. 6A shows an exemplary exploded diagram of a gas connector systemthat includes two gas connections side-by-side and a common compliantsealing element.

One port 610 includes a barbed connection and the other connector is asmaller diameter straight port that allows for the ports to overlap inlength to minimize space between the elements 610 while still allowingthe elements to be separated by a radial distance to provide a compliantconnection that minimizes transmission of noise and vibration betweenelements.

FIG. 6B depicts an exemplary embodiment of the gas connector system whenit is assembled and illustrates the overlapping port lengths and captiveends of the common compliant member 620.

Compliant common member 620 may be comprised of a compliant elastomericmaterial such as silicone, viton, EPDM, or rubber. The compliant membermay additionally contain lead-in chamfers or radiuses 630 and has endsthat are captured between port elements 610 so that the tube cannot bedislodged after assembly and also ensures a repeatable position of allcomponents.

FIG. 6C shows an alternate example while FIGS. 6D and 6E show an examplegas connector where one end of the connection is to integrated sensorblock assembly 300 and the other end is a product valve manifold.

FIG. 7 is directed to the airflow through exemplary concentrator 100.Air enters through a ducted air intake 710 on the intake side of the fan720. Ambient air passes through the fan and is discharged at a positivepressure, whereby a portion of the fan discharge air is directed toadditional ducting that ports the air to the compressor intake filter730 wherein it is filtered by passing through the filter media anddirected to the compressor 2 through compliant vibration mounts and airintake ports 740.

The portion of the fan discharge air that is not directed to thecompressor intake, passes over the exterior of compressor 2 and downthrough exhaust vents 750.

Fan discharge air may be directed to the cylinders of the reciprocatingpiston compressor depicted in one embodiment to maintain beneficialcooling of the piston seal moving inside the cylinder. The speed of theair mover may be varied based on the compressor speed, the accumulatorpressure, or any combination of speed, pressure, and/or temperature. Therate of fan discharge may be controlled proportionally to the amount ofwork being done by the compressor, as measured by speed, pressure, orpower. A direct measurement of compressor temperature may be made via athermistor or a reflective temperature measurement. Alternately oradditionally. the concentrator ambient temperature, the ambienttemperature around the compressor or elsewhere in the concentrator, orthe output gas temperature may be used. A target value for temperaturethat results in beneficial compressor efficiency or seal or bearing lifewhile maintaining acceptable sound levels, or any combination thereofmay be stored in the microcontroller. Discreet levels of fan speed maybe stored in a lookup table based on various threshold values for any ofthe above values; alternatively an equation orproportional-integral-derivative control loop may be implemented.

The embodiments described herein are exemplary. Modifications,rearrangements, substitute processes, alternative elements, etc. may bemade to these embodiments and still be encompassed within the teachingsset forth herein. One or more of the processes described herein may becarried out by one or more processing and/or digital devices, suitablyprogrammed.

The various illustrative processing, data display, and user interfacesdescribed in connection with the embodiments disclosed herein can beimplemented as electronic hardware, computer software, or combinationsof both. To clearly illustrate this interchangeability of hardware andsoftware, various illustrative components, blocks, and modules have beendescribed above generally in terms of their functionality. Whether suchfunctionality is implemented as hardware or software depends upon theparticular application and design constraints imposed on the overallsystem. The described functionality can be implemented in varying waysfor each particular application, but such implementation decisionsshould not be interpreted as causing a departure from the scope of thedisclosure.

The various illustrative logical blocks and modules described inconnection with the embodiments disclosed herein can be implemented orperformed by a machine, such as a processor configured with specificinstructions, a digital signal processor (DSP), an application specificintegrated circuit (ASIC), a field programmable gate array (FPGA) orother programmable logic device, discrete gate or transistor logic,discrete hardware components, or any combination thereof designed toperform the functions described herein. A processor can be amicroprocessor, but in the alternative, the processor can be acontroller, microcontroller, or state machine, combinations of the same,or the like. A processor can also be implemented as a combination ofcomputing devices, e.g., a combination of a DSP and a microprocessor, aplurality of microprocessors, one or more microprocessors in conjunctionwith a DSP core, or any other such configuration.

The elements of the embodiments disclosed herein can be embodieddirectly in hardware, in a software module executed by a processor, orin a combination of the two. A software module can reside in RAM memory,flash memory, ROM memory, EPROM memory, EEPROM memory, registers, harddisk, a removable disk, a CD-ROM, or any other form of computer-readablestorage medium known in the art. An exemplary storage medium can becoupled to the processor such that the processor can read informationfrom, and write information to, the storage medium. In the alternative,the storage medium can be integral to the processor. The processor andthe storage medium can reside in an ASIC. A software module can comprisecomputer-executable instructions which cause a hardware processor toexecute the computer-executable instructions.

Conditional language used herein, such as, among others, “can,” “might,”“may,” “e.g.,” and the like, unless specifically stated otherwise, orotherwise understood within the context as used, is generally intendedto convey that certain embodiments include, while other embodiments donot include, certain features, elements and/or states. Thus, suchconditional language is not generally intended to imply that features,elements and/or states are in any way required for one or moreembodiments or that one or more embodiments necessarily include logicfor deciding, with or without author input or prompting, whether thesefeatures, elements and/or states are included or are to be performed inany particular embodiment. The terms “comprising,” “including,”“having,” “involving,” and the like are synonymous and are usedinclusively, in an open-ended fashion, and do not exclude additionalelements, features, acts, operations, and so forth. Also, the term “or”is used in its inclusive sense (and not in its exclusive sense) so thatwhen used, for example, to connect a list of elements, the term “or”means one, some, or all of the elements in the list.

Disjunctive language such as the phrase “at least one of X, Y or Z,”unless specifically stated otherwise, is otherwise understood with thecontext as used in general to present that an item, term, etc., may beeither X, Y or Z, or any combination thereof (e.g., X, Y and/or Z).Thus, such disjunctive language is not generally intended to, and shouldnot, imply that certain embodiments require at least one of X, at leastone of Y or at least one of Z to each be present.

The terms “about” or “approximate” and the like are synonymous and areused to indicate that the value modified by the term has an understoodrange associated with it, where the range can be ±20%, ±15%, ±10%, ±5%,or ±1%. The term “substantially” is used to indicate that a result(e.g., measurement value) is close to a targeted value, where close canmean, for example, the result is within 80% of the value, within 90% ofthe value, within 95% of the value, or within 99% of the value.

Unless otherwise explicitly stated, articles such as “a” or “an” shouldgenerally be interpreted to include one or more described items.Accordingly, phrases such as “a device configured to” are intended toinclude one or more recited devices. Such one or more recited devicescan also be collectively configured to carry out the stated recitations.For example, “a processor configured to carry out recitations A, B andC” can include a first processor configured to carry out recitation Aworking in conjunction with a second processor configured to carry outrecitations B and C.

While the above detailed description has shown, described, and pointedout novel features as applied to illustrative embodiments, it will beunderstood that various omissions, substitutions, and changes in theform and details of the devices illustrated can be made withoutdeparting from the spirit of the disclosure. As will be recognized,certain embodiments described herein can be embodied within a form thatdoes not provide all of the features and benefits set forth herein, assome features can be used or practiced separately from others. Allchanges which come within the meaning and range of equivalency of theclaims are to be embraced within their scope.

1. An assembly for an oxygen concentrator comprising: an accumulator; anoxygen sensor disposed to sample gas directed to the patient gas outletof a gas concentrator; a pressure sensor disposed to sample gas in theaccumulator; a breath sensor disposed to sample gas at a patient gasoutlet of the gas concentrator; an electronic circuit, and, gas ports tothe sensors and the accumulator wherein; the sensors are at least one ofassembled onto an electronic circuit or directly into a body whichincludes the accumulator volume; and, the circuit is assembled onto thebody making at least one of direct sealed gas or electrical connectionsto the sensors;
 2. The assembly of claim 1, wherein the inlet ports areconnectable to a concentrator valve manifold system.
 3. The assembly ofclaim 1, further comprising at least one of a display or user interfaceas part of the electronic circuit.
 4. The assembly of claim 1, furthercomprising at least one of a gas output filter or cannula connection tothe patient gas path, and associated inlet and outlet ports from thecannula connection to the element.
 5. The assembly of claim 2, furthercomprising a temperature sensor disposed to sample gas in theaccumulator.